19672 research outputs found
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Assessing regional left ventricular thickening dysfunction and dyssynchrony via personalized modeling and 3D wall thickness measurements for acute myocardial infarction
No full textBackground: Existing clinical diagnostic and assessment methods could be improved to facilitate early detection and treatment of cardiac dysfunction associated with acute myocardial infarction (AMI) to reduce morbidity and mortality. Purpose: To develop 3D personalized left ventricular (LV) models and thickening assessment framework for assessing regional wall thickening dysfunction and dyssynchrony in AMI patients. Study Type: Retrospective study, diagnostic accuracy. Subjects: Forty-four subjects consisting of 15 healthy subjects and 29 AMI patients. Field Strength/Sequence: 1.5T/steady-state free precession cine MRI scans; LGE MRI scans. Assessment: Quantitative thickening measurements across all cardiac phases were correlated and validated against clinical evaluation of infarct transmurality by an experienced cardiac radiologist based on the American Heart Association (AHA) 17-segment model. Statistical Test: Nonparametric 2-k related sample-based Kruskal–Wallis test; Mann–Whitney U-test; Pearson's correlation coefficient. Results: Healthy LV wall segments undergo significant wall thickening (P 50% transmurality) underwent remarkable wall thinning during contraction (thickening index [TI] = 1.46 ± 0.26 mm) as opposed to healthy myocardium (TI = 4.01 ± 1.04 mm). For AMI patients, LV that showed signs of thinning were found to be associated with a significantly higher percentage of dyssynchrony as compared with healthy subjects (dyssynchrony index [DI] = 15.0 ± 5.0% vs. 7.5 ± 2.0%, P < 0.01). Also, a strong correlation was found between our TI and left ventricular ejection fraction (LVEF) (r = 0.892, P < 0.01), and moderate correlation between DI and LVEF (r = 0.494, P < 0.01). Data Conclusion: The extracted regional wall thickening and DIs are shown to be strongly correlated with infarct severity, therefore suggestive of possible practical clinical utility. Level of Evidence: 2. Technical Efficacy: Stage 1. J. Magn. Reson. Imaging 2019;49:1006–1019. © 2018 International Society for Magnetic Resonance in Medicin
An autoethnographic report on freelance employment in the Malaysian oil and gas industry during uncertain economic conditions
No full textIn this paper we present our study of the role of freelancers in the modern labour market, especially during times of economic downturns. Using an autoethnographic research approach, it presents the personal journey of Fathullah working as a consultant in the oil and gas industry in Malaysia. The study focuses on the impact of the 2014 oil price crash and his subsequent plight in taking his career forward during times of uncertainty. Based on the autoethnographic account, it explores various aspects of life as a freelancer such as the issues of job security and job satisfaction. Fathullah found that he enjoyed a different form of job security compared to the time when he was in regular employment, for he has direct market access and wider reach to organizations that require his skills. It follows that he also experienced better job satisfaction as a freelancer. This paper provides insights to aspiring job seekers, businesses in need of human capital and policy-makers aiming to modernize the labour market. Copyright 2019: Fathullah Akmal Khalid, Wai Meng Chan, Azlina Abdul Jalil, and Nova Southeastern University
Mechanosynthesis of N-Methyl Imines Using Recyclable Imidazole-Based Acid-Scavenger: In Situ Formed Ionic Liquid as Catalyst and Dehydrating Agent
No full text1,1′-(1,4-Butanediyl)bis(imidazole) was prepared by a modified method and its application as an efficient promoter was demonstrated for the mechanosynthesis of N-methyl imines using ball milling as a non-conventional process under solvent-free conditions. In this new protocol design, the bis-imidazole acted as a recyclable acid-scavenging agent. This efficient approach to the N-methyl imines displays a combination of the synthetic virtues of a non-conventional condensation reaction with ecological benefits and convenience of a facile mechanosynthetic process. The current method has advantages such as reduced waste by avoiding solvent, exclusion of hazardous materials during the reaction, elimination of handling an anhydrous gas in an evacuated container or a solution of methylamine in ethanol, good yields for relatively unreactive benzaldehydes containing electron-donating substituents, short reaction times, and metal- and acid-free conditions. Furthermore, the promoter was easily regenerated and reused several times with no significant loss of activity. © 2019 CSIRO
Reducing the Crystallite Size of Spherulites in PEO-Based Polymer Nanocomposites Mediated by Carbon Nanodots and Ag Nanoparticles
No full textThe PEO-based polymer nanocomposites were prepared by solution cast method. Green approaches were used for synthesis of carbon nanodots (CNDs) and silver nanoparticles (Ag NPs). It was found that the crystallite size of spherulites of PEO was greatly scarified upon incorporation of CNDs and Ag NPs. In the present work, in opposition to other studies, broadening of surface plasmon resonance (SPR) peak of metallic Ag NPs in PEO-based polymer composites was observed rather than peak tuning. Various techniques, such as powder X-ray diffraction (XRD), SEM, UV–Vis spectroscopy, and photoluminescence (PL), were used to characterize the structural, morphological, and optical properties of the samples. Increase of amorphous phase for the PEO doped with CND particles was shown from the results of XRD analyses. Upon the addition of suspended Ag NPs to the PEO:CNDs composites, significant change of XRD peak position was seen. A field-emission scanning electron microscope (FESEM) was used to investigate the surface morphology of the samples. In the SEM, a significant change in the crystalline structure was seen. The size of PEO spherulites in the PEO nanocomposite samples became smaller and the percentage of amorphous portion became larger, owing to the distribution of CNDs and Ag NPs. The UV–Vis absorption spectra of the PEO-based polymer were found to improve and shift to higher wavelengths upon incorporation of CNDs and Ag NPs into the PEO matrix. The SPR peak broadening in the UV–Vis spectra was observed in the PEO:CNDs composites due to the Ag NPs. The absorption edge value of PEO was found to shift toward lower photon energy as the CNDs and Ag NPs are introduced. The photoluminescence (PL) spectra were also observed for the PEO:CNDs and PEO:CNDs:Ag samples and found to be more intense in the PEO:CNDs system than in the PEO:CNDs:Ag system. Lastly, the optical band gap of the samples was further studied in detail using of Tauc’s model and optical dielectric loss parameter. The types of electron transition were specified. © 2019 by the authors. Licensee MDPI, Basel, Switzerland
Neuroprotective potential of Spirulina platensis on lesioned spinal cord corticospinal tract under experimental conditions in rat models
No full textSpinal cord injury (SCI) results from penetrating or compressive traumatic injury to the spine in humans or by the surgical compression of the spinal cord in experimental animals. In this study, the neuroprotective potential of Spirulina platensis was investigated on ultrastructural and functional recovery of the spinal cord following surgical-induced injury. Twenty-four Sprague-Dawley rats were divided into three groups; sham group, control (trauma) group, and experimental (S. platensis) group (180 mg/kg) of eight rats each. For each group, the rats were then subdivided into two groups to allow measurement at two different timepoints (day 14 and 28) for the microscopic analysis. Rats in the control and experimental S. platensis groups were subjected to partial crush injury at the level of T12 with Inox number 2 modified forceps by compressing on the spinal cord for 30 s. Pairwise comparisons of ultrastructural grading mean scores difference between the control and experimental S. platensis groups reveals that there were significant differences on the axonal ultrastructure, myelin sheath and BBB Score on Day 28; these correlate with the functional locomotor recovery at this timepoint. The results suggest that supplementation with S. platensis induces functional recovery and effective preservation of the spinal cord ultrastructure after SCI. These findings will open new potential avenue for further research into the mechanism of S. platensis-mediated spinal cord repair. © 2019, © 2019 Taylor & Francis Group, LLC
Malaysian early career researchers on the ethics of scholarly publishing
No full textPublication ethics are rarely taught. This paper presents research into the knowledge of scholarly publishing ethics among Malaysian early-career researchers (ECRs). This research comes from year two of a projected three-year-long study of ECRs from seven countries (China, France, Malaysia, Poland, Spain, the UK, and the US), for which semi-structured in-depth interviews were conducted with study participants. For the findings reported in this paper, 12 ECRs from science and social science disciplines at five Malaysian research-intensive universities were interviewed during the period from February to June 2017. The interview record was compared with the previous year's (2016) record to identify changes in interviewees' responses to a set of questions on their knowledge of ethics in scholarly communication. In addition, contextual data were obtained from the CVs of the ECRs. Our findings indicate that the attitudes and behaviours of Malaysian ECRs in relation to scholarly communication ethics have changed in the passage of one year. We observed noteworthy changes in ECRs' knowledge of unethical behaviours. As compared with data from 2016, the ECRs are more verbose in their responses on what is generally regarded as ethical and unethical in research and/or publishing practices. Authorship policies, the academic evaluation system, and the scrutiny which will keep the lid on any unethical behaviours are the most important factors bringing about the changes we observed. This paper suggests that ECRs' manifestation of publishing ethics is gauged through their publishing practices. © 2019 Malaysian Journal of Library & Information Science
Effect of the oxidation process on the molecular interaction of polyaromatic hydrocarbons (PAH) with carbon nanotubes: Adsorption kinetic and isotherm study
No full textAgglomeration is a major setback in the use of pristine multiwall carbon nanotube for many applications. Therefore, application of hydroxyl functionalized multiwall carbon nanotubes (MWCNT-OH) for the removal of naphthalene and fluorine was investigated and compared with pristine MWCNT for the first time. FTIR, BET, TGA, SEM, and TEM were used to investigate the functional group, microstructure and morphology of MWCNT and MWCNT-OH. The BET results showed more mesoporosity for MWCNT-OH than MWCNT. Batch equilibrium adsorption data were fitted to the Langmuir, Freundlich and Temkin models, of which the Langmuir model exhibited the best fit. The correlation of Langmuir model for naphthalene adsorption on MWCNT-OH was observed to be higher (i.e. R2 = 0.9703 for MWCNT-OH and R2 = 0.5082 for MWCNT) while the correlation for adsorption of flourene is higher for MWCNT (i.e. R2 = 0.998 for MWCNT and R2 = 0.9517 for MWCNT-OH). The maximum adsorption capacity (qe) for MWCNT-OH (57.401 ng/g-356.121 ng/g for naph and 61.235 ng/g - 367.361 ng/g for fluorene) was generally higher and more stable for lower concentration ranges while it is comparable with MWCNT (48.177 ng/g - 354.00 ng/g for naph and 59.635 ng/g- 366.709 ng/g for fluorene) at higher concentration. The qe calculated (344.828 ng/g for naph and 357.143 ng/g for fluorene) using PSO was observed to be much closer to experimental qe (356.121 ng/g for naph and 367.361 ng/g for fluorine) for MWCNT-OH adsorbent than MWCNT (cal qe are 384.615 ng/g for naph and 400.000 ng/g for fluorene; exp qe 354.00 ng/g for naph and 366.709 ng/g for fluorene). The value of boundary layer thickness, is >0, this indicates the reaction process is quite complex and is not solely controlled by the intra-particle diffusion. The results of this study indicate the high potential of the developed MWCNT-OH adsorbent as an efficient and successful material for the removal of carcinogenic PAHs from the water body. © 2019 Elsevier B.V
Malaysia’s stance towards Trump’s decision regarding Bayt al-Maqdis
Get PDFBayt al-Maqdis is a territory that is always conflicted in dispute due to the prolonged crisis of land ownership between Palestine and Israel. From an Islamic perspective, Bayt al-Maqdis is an important territory due to its status as a Holy Land to the Muslims as therein lies the Al-Aqsa Mosque, which is the third holiest mosque after Masjid al-Haram and Masjid al Nabawi (Nor, 2010: 83). This warrants much attention from Islamic countries specifically towards Bayt al-Maqdis (Nor & Rozi, 2016)
A Novel Liquid Chromatography Tandem Mass Spectrometry Technique using Multi-Period-Multi-Experiment of MRM-EPI-MRM3 with Library Matching for Simultaneous Determination of Amphetamine Type Stimulants Related Drugs in Whole Blood, Urine and Dried Blood Stain (DBS)—Application to Forensic Toxicology Cases in Malaysia
No full textA novel mass spectrometry detection technique based on a multi-period and multi- experiment (MRM-EPI-MRM3) with library matching in a single run for fast and rapid screening and identification of amphetamine type stimulants (ATS) related drugs in whole blood, urine and dried blood stain was developed and validated. The ATS-related drugs analyzed in this study include ephedrine, pseudoephedrine, amphetamine, methamphetamine, MDMA (3,4-Methylenedioxymethamphetamine), MDA (3,4-Methylenedioxyamphetamine), MDEA (3,4-Methylenedioxy-N-ethylamphetamine) and phentermine. The relative standard deviation for inter and intraday was less than 15% while recoveries ranged from 80% to 120% for all three matrices, i.e., whole blood, urine and dried blood stain. All compounds gave library matching percentage of more than 85% based on the purity. This method was proven to be simple and robust, and provide high confident results complemented with library matching confirmation
Maintenance work for heritage buildings in Malaysia: owners’ perspectives
No full textPurpose: The purpose of this paper is to establish the impacts of good maintenance work for heritage buildings in Malaysia. This purpose is achieved through identifying factors that lead to the lack of maintenance of heritage buildings, establishing strategies to overcome the lack of maintenance of heritage buildings and analyzing the impact of good maintenance work on heritage buildings in Malaysia. Design/methodology/approach: A quantitative method was employed for this study to identify the variables that most influence the maintenance of heritage buildings in Malaysia. The respondents were the owners of the heritage buildings in Peninsular Malaysia. There were 65 owners of heritage buildings identified from the official website of the Department of National Heritage, Ministry of Tourism and Culture, Malaysia. Simple random sampling was used to obtain the sample size of the targeted respondent. A total of 56 questionnaire surveys were distributed to the owners of heritage buildings. In total, 37 respondents returned the completed questionnaires, resulting in a response rate of 66 percent. The data were analyzed by Descriptive Statistics using Statistical Package for the Social Science software version 20. Findings: Results show that the factors that lead to the lack of maintenance of heritage buildings are limited finance, the absence of maintenance guideline and ill-defined maintenance policy. The strategies to overcome the problem include providing a financial budget by the respective authorities, establishing a standard maintenance guideline and revising the existing policy. Research limitations/implications: The paper is limited to the identification of factors that lead to a lack of maintenance and strategies to overcome the problem for the heritage buildings in Malaysia. The respondents are the owners of heritage buildings in Malaysia. The focus is given to them due to the fact that it will help them in understanding the importance of managing and operating for their buildings. Practical implications: The results offer value-added information to building managers who are responsible for maintaining heritage buildings. Findings show that good maintenance work on heritage buildings can enhance the value and safety of the building as well as preventing heritage buildings from deteriorating. Social implications: The quality of maintenance could be enhanced by focusing on the important variables that affect the quality of maintenance works of heritage buildings. Originality/value: Limited studies had been carried out in the context of the maintenance of heritage buildings, especially in Malaysia